StoX

2TB Western Digital 3.5-inch single-disk (WD20EADS)

Recommended Posts

It is surprising the number of people on a disk drive forum who don't know the difference between the base 2 and base 10 number systems, and who therefore don't know how hard drive sizes are measured.

Could you please explain the reason for your post? I fail to see any relevance to any post within this topic. Seeing as it comes immediately after my post discussing tebibytes and terabytes, perhaps you’d like to point out where I’ve gone wrong?

Tebibytes, or "Computing" terabytes if you prefer, use a binary (base 2) system where Kilo, Mega, Giga, Tera etc. are all representative of powers of 1024 (1024, 1024^2, 1024^3, etc.). This is used to determine maximum addressable space for RAM, HDDs, etc.

Terabytes, or "SI / standard" terabytes if you prefer, use a base 10 system where the prefixes represent powers of 1000. This is used by HDD manufacturers to specify size, in communications to represent data rates in bits per second, and by most scientists and the rest of the world when applied to SI units (Kilometres, Gigahertz, etc.).

JF2000 was noting that many don't know which system is used in which area of computing. The terms Tebibyte, etc. were introduced to combat this confusion, but since everyone was used to the old notation, hardly anyone bothers to use the new terms, preferring to let the context dictate which system is in use. And most of the time it doesn't matter, except that a 2 TB hard disk drive (as marketed by HDD makers) won't hold 2 TB of files (as reported by operating systems).

So hdman, you were correct in your post - the inaccuracy was in the WD site, as you pointed out. JF2000 inaccurately attributed the quote to a disk drive forum, which I think is what caused your confusion.

So, now that's all cleared up (in my usual clear as mud style), we'll now return to our scheduled programming. ;)

It makes sense that the drive should be 5400 RPM, it must be easier to read higher data density platters when they're moving past more slowly.

Share this post


Link to post
Share on other sites
So hdman, you were correct in your post - the inaccuracy was in the WD site, as you pointed out. JF2000 inaccurately attributed the quote to a disk drive forum, which I think is what caused your confusion.

Oh, I never considered that possibility, thanks for pointing it out Spod! And no hard feelings, jf2000. It only bothered me that staff working for WD made such a blunder in their Knowledge Base, and it still hasn’t been corrected.

Good to see it’s been officially announced. :)

Share this post


Link to post
Share on other sites

Little bit off topic, but can somebody tell me, how can I recognize 1 TB Green HDD from WD, with 2 500GB platters and 32 MB Cache. I found of WD website, there is a 2.0 TB, 1.5TB and 1.0 TB versions. But when I see WD10EADS tests, there is always mentioned that this drive utilizes a higher areal density to store one terabyte on only three platters. But I wanna have 1TB with 2-platters. Is there any further code behind the EADS mark, pointing to 2 platters design?

Share this post


Link to post
Share on other sites

WD is notorious for hiding the actual drive configuration inside their model #s. if you want confirmation I suspect you'll have a while to wait.

Either that or order a couple of drives from a couple of different retailers, then stick 'em on a scale. The lighter ones probably have fewer platters. :P

Share this post


Link to post
Share on other sites

Newegg just added the 2 TB drive:

http://www.newegg.com/Product/Product.aspx...N82E16822136344

No sign from the 1.5 TB model.

Don't purchase before you can see some real reviews!!!!

And it's too way expensive. The Seagate (1.5 TB), even if it's not reliable (too much defective units) it's available for US$ 130. In the first month of release, it was priced US$ 215/200. So, let's wait at least 3 months, until we can get proper reviews and a much better price... :P

Share this post


Link to post
Share on other sites

HERE IS A SUMMARY (EXCERPTS) FROM SOME REVIEWS:

Western Digital 2TB Caviar Green Drive Preview

A quick glance at the numbers here show this new big-boy Caviar Green drive from WD offering more than competitive performance versus the likes of Samsung's Spinpoint F1 and Seagate's Barracuda 7200.11 -- both 7200RPM-based products. HD Tach shows an average read speed of 90MB/s and average writes at 80MB/s.

http://hothardware.com/News/WD-2TB-Caviar-...-Drive-Preview/

2 TB Hard Drive Preview: Western Digital WD20EADS

These benchmarks were run on an engineering sample, so we're not assigning a rating yet. But we're pretty impressed with the overall performance, lack of heat, and relatively quiet operation. The new WD20EADS is really terabytes for the masses: affordable, capacious, and efficient.

http://www.extremetech.com/print_article2/...3D236483,00.asp

Western Digital Caviar Green 2TB hard drive

This certainly pays off in terms of the sound and vibration levels. The Green has a reasonable idle noise level of 25dBA that only steps up to 29dBA under load. Those noise ratings fall between a typical 7200rpm drive and a really quiet 5400rpm unit, which is a testament to WD as packing four platters into a drive is a sure-fire way to raise noise levels.

http://www.reghardware.co.uk/2009/01/27/re...aviar_green_2tb

All we know is that we can hardly wait for a 2TB Caviar Black with 7200rpm spindle speed.

Verdict

WD’s new 2TB Caviar Green is surprisingly fast yet it's also very quiet. Besides, what self-respecting power PC owner doesn't want a 2TB drive?

http://www.reghardware.co.uk/2009/01/27/re..._2tb/page5.html

Western Digital Caviar Green 2 TB Retail Desktop Drive

The power saving features that Western Digital has incorporated into their Green Series products is very impressive. For enthusiasts it doesn’t matter too much if your storage drives use 3 watts less power than a competing product when you are already using 250 watts for your graphics card, 160 from your processor and who knows how much more power from your array of VelociRaptors. Having 2TB of storage in an external enclosure that doesn’t require active cooling is a positive, no matter what kind of user you are. And I am sure in time WDC will take advantage of the new drives and make some popular My Book products with the new technology.

http://www.tweaktown.com/reviews/1738/10/w...rive/index.html

Western Digital Caviar Green 2TB

Verdict

Western Digital is first to the 2TB party and it has made an impressive entrance. While it's no performance demon, the WD Caviar Green 2TB has all the power saving credentials that we now crave, is quiet, and is sensibly priced.

http://www.trustedreviews.com/storage/revi...ar-Green-2TB/p3

Got my WD 2TB! Pics and benchmarks inside.

One other thing I have to admit, this drive is quiet and cold. Even in the random seek tests, I can't hear it over my case fans. (although that's not saying much) I thought the original benches showing 26c were just because the drive was still cold from shipping. But it's been running for 2 hours now, idling at 24c. It went up to 27c during the write test. For reference, room temperature is 21c and the drives have a 120mm fan blowing directly across them. My Velociraptor idles at 41c.

http://hardforum.com/showthread.php?p=1033...#post1033667758

Share this post


Link to post
Share on other sites
WD Caviar® Green™

SATA Hard Drives

2 TB, 32 MB Cache, SATA 3 Gb/s

Cool, quiet, eco-friendly.

Did nobody even noticed that the "Non-recoverable read errors per bits read" is still 1 per 10exp15 bits despite the 10exp10bits on the drive ?

This means this drive is too large to be safe in a large raid array...may be staying below 4+2 raid 6 drives (= 8TB) will be ok.

Edited by HachavBanav

Share this post


Link to post
Share on other sites
WD Caviar® Green™

SATA Hard Drives

2 TB, 32 MB Cache, SATA 3 Gb/s

Cool, quiet, eco-friendly.

Did nobody even noticed that the "Non-recoverable read errors per bits read" is still 1 per 10exp15 bits despite the 10exp10bits on the drive ?

This means this drive is too large to be safe in a large raid array...may be staying below 4+2 raid 6 drives (= 8TB) will be ok.

This drive is 2 terabytes, which is 16 terabits, which is 16exp12 bits. You would have to read the data on the drive, on average, over 600 times before coming up to an error.

Though that's still rather bothersome. WD is probably just using the rating for the older generation and doesn't have data yet for the new one. Rest assured, I'm fairly sure these error rates are very cautious.

Share this post


Link to post
Share on other sites

From what I understand, the impact of unrecoverable-read-error rates on array rebuilds (for parity-based arrays) is a factor of the total data size of the array, not the size of each disk.

EG, an array of 11 1TB drives in RAID5 (10TB total size), when rebuilding, must read all 10TB from the good drives.

An array of 6 2TB drives in RAID5 (10TB total size) would be reading the same amount of data. So it is just as likely (or unlikely) to encounter an unrecoverable read error during that process.

Having roughly half as many drives, it is less likely to fail in the first place, and also less likely to suffer a 2nd failure (and hence data loss) during the rebuild.

If you decide to make a 20TB RAID5 (11x 2TB drives), then yes, the overall chance for a read error during recover is 2x what it was in the old 10TB array. But it would have been with a 21x 1TB array anyway (and a 21-disk RAID5 would be un-smart from the outset).

For mirror-based arrays, using the larger drives does increase the expected read-error rate during a rebuild, regardless of array size. However you're in better shape should that happen, as the array can tolerate further drive failures (as long as it's not the partner drive of the failed one).

Share this post


Link to post
Share on other sites
With the launch of this drive seemingly imminent, look what has appeared on the WD support site:
2 TB drives do not work on existing operating systems.

Question

Does 2 TB and greater hard drives work on existing operating systems?

Answer

Hard drives 2 TB and greater are not currently supported with the present implementation of Master Boot Record (MBR) partitioning.

http://wdc.custhelp.com/cgi-bin/wdc.cfg/ph...hp?p_faqid=2754

They should know better than this. The issue is the 2 Tebibyte (TiB) partition limit with MBR. A 2 Terabyte drive falls short of this (1.82 TiB). It’s not as though the limit is 2 TB and they’re making 2 TiB drives!

And why would they bring this up now? I doubt we’ll be seeing 3 TB drives for some time.

I'm looking forward to seeing a drive >2TiB, so...what will need to be done? will it simply mean applying an update to one's operating system? and BIOS?

thanks, coyote

Edited by coyote

Share this post


Link to post
Share on other sites

It's a combination of an OS configuration as well as a drive firmware setup conflict, I don't know of too many here with this drive yet so I'm not sure...?

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now